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N-terminal Deletion (n-terminal + deletion)
Selected AbstractsThe C-terminal region of CHD3/ZFH interacts with the CIDD region of the Ets transcription factor ERM and represses transcription of the human presenilin 1 geneFEBS JOURNAL, Issue 6 2007Martine Pastorcic Presenilins are required for the function of ,-secretase: a multiprotein complex implicated in the development of Alzheimer's disease (AD). We analyzed expression of the presenilin 1 (PS1) gene. We show that ERM recognizes avian erythroblastosis virus E26 oncogene homolog (Ets) motifs on the PS1 promoter located at ,10, +90, +129 and +165, and activates PS1 transcription with promoter fragments containing or not the ,10 Ets site. Using yeast two-hybrid selection we identified interactions between the chromatin remodeling factor CHD3/ZFH and the C-terminal 415 amino acids of ERM used as bait. Clones contained the C-terminal region of CHD3 starting from amino acid 1676. This C-terminal fragment (amino acids 1676,2000) repressed transcription of the PS1 gene in transfection assays and PS1 protein expression from the endogenous gene in SH-SY5Y cells. In cells transfected with both CHD3 and ERM, activation of PS1 transcription by ERM was eliminated with increasing levels of CHD3. Progressive N-terminal deletions of CHD3 fragment (amino acids 1676,2000) indicated that sequences crucial for repression of PS1 and interactions with ERM in yeast two-hybrid assays are located between amino acids 1862 and 1877. This was correlated by the effect of progressive C-terminal deletions of CHD3, which indicated that sequences required for repression of PS1 lie between amino acids 1955 and 1877. Similarly, deletion to amino acid 1889 eliminated binding in yeast two-hybrid assays. Testing various shorter fragments of ERM as bait indicated that the region essential for binding CHD3/ZFH is within the amino acid region 96,349, which contains the central inhibitory DNA-binding domain (CIDD) of ERM. N-Terminal deletions of ERM showed that residues between amino acids 200 and 343 are required for binding to CHD3 (1676,2000) and C-terminal deletions of ERM indicated that amino acids 279,299 are also required. Furthermore, data from chromatin immunoprecipitation (ChIP) indicate that CHD3/ZFH interacts with the PS1 promoter in vivo. [source] Receptors for calcitonin gene-related peptide and adrenomedullin: implications for skin cell biologyEXPERIMENTAL DERMATOLOGY, Issue 9 2004J. A. Fischer The specificity of a G-protein-coupled calcitonin receptor (CTR) and a CT receptor-like receptor (CLR) for calcitonin gene-related peptide (CGRP), adrenomedullin (AM) and amylin is defined by the heterodimeric non-covalent association with three receptor-activity-modifying proteins (RAMPs). Chemical cross-linking of proteins at the cell surface and immunoprecipitation have identified [125I]CGRP/CLR/RAMP1, [125I]AM/CLR/RAMP2 and -3 as well as [125I]CGRP/CTR/RAMP1, [125I]amylin/CTR/RAMP1 and -RAMP3 complexes. CLR/RAMP1 defines a CGRP receptor. CLR/RAMP2 and -3 correspond to AM1 and AM2 receptor isotypes, respectively. The AM1 receptor cross-reacts with CGRP at high and the AM2 receptor at low concentrations. With the N-terminal deletion of amino acids 14,20 of the mouse, CLR-selective inactivation of AM over CGRP receptor function was obtained. As a result, functional interaction with AM was no longer possible. Overexpression of the CLR in transgenic mice together with the endogenous RAMP2 results in thinning of the hairs during postnatal development (L. M. Ittner et al. conference poster). In conclusion, the extreme N-terminus of the CLR and the extracellular N-terminal domains of RAMP1 and -2 contain amino acid residues that provide AM- or CGRP-binding selectivity of the CLR/RAMP complexes. Hair development is attenuated, resulting in the thinning of the hairs and eventually alopecia during postnatal development. [source] Modulation of F1 hybrid stature without altering parent plants through trans-activated expression of a mutated rice GAI homologuePLANT BIOTECHNOLOGY JOURNAL, Issue 2 2005Ning Su Summary Hybrid breeding, by taking advantage of heterosis, brings about many superior properties to the F1 progeny. However, some properties, such as increased plant height, are not desirable for agronomic purposes. To specifically counter the height increase associated with hybrid progeny, we employed an Arabidopsis model and tested a trans-activation system for specifically expressing a mutated GAI gene only in the F1 hybrid plants to reduce plant stature. A transcriptional activator, the Gal4 DNA-binding domain fused to the acidic activation domain of herpes simplex virus VP16 protein, driven by a maize ubiquitin promoter, was introduced in one parental line. A rice GAI homologue with an N-terminal deletion of the DELLA domain, driven by a promoter that is responsive to the transcriptional activator, was transferred into another parental line. After genetic crossing, trans-activation of the GAI mutant gene resulted in a dwarf phenotype. Over 50 pair-wise crosses between the parental lines were performed, and analyses suggested that the percentage of F1 progeny exhibiting dwarfism ranged from about 25% to 100%. Furthermore, the dwarfism trait introduced in F1 progeny did not seem to affect total seed yield. Our result suggests the feasibility of manipulating F1 hybrid progeny traits without affecting parent plants or the agronomic property of the progeny. [source] The C-terminal region of CHD3/ZFH interacts with the CIDD region of the Ets transcription factor ERM and represses transcription of the human presenilin 1 geneFEBS JOURNAL, Issue 6 2007Martine Pastorcic Presenilins are required for the function of ,-secretase: a multiprotein complex implicated in the development of Alzheimer's disease (AD). We analyzed expression of the presenilin 1 (PS1) gene. We show that ERM recognizes avian erythroblastosis virus E26 oncogene homolog (Ets) motifs on the PS1 promoter located at ,10, +90, +129 and +165, and activates PS1 transcription with promoter fragments containing or not the ,10 Ets site. Using yeast two-hybrid selection we identified interactions between the chromatin remodeling factor CHD3/ZFH and the C-terminal 415 amino acids of ERM used as bait. Clones contained the C-terminal region of CHD3 starting from amino acid 1676. This C-terminal fragment (amino acids 1676,2000) repressed transcription of the PS1 gene in transfection assays and PS1 protein expression from the endogenous gene in SH-SY5Y cells. In cells transfected with both CHD3 and ERM, activation of PS1 transcription by ERM was eliminated with increasing levels of CHD3. Progressive N-terminal deletions of CHD3 fragment (amino acids 1676,2000) indicated that sequences crucial for repression of PS1 and interactions with ERM in yeast two-hybrid assays are located between amino acids 1862 and 1877. This was correlated by the effect of progressive C-terminal deletions of CHD3, which indicated that sequences required for repression of PS1 lie between amino acids 1955 and 1877. Similarly, deletion to amino acid 1889 eliminated binding in yeast two-hybrid assays. Testing various shorter fragments of ERM as bait indicated that the region essential for binding CHD3/ZFH is within the amino acid region 96,349, which contains the central inhibitory DNA-binding domain (CIDD) of ERM. N-Terminal deletions of ERM showed that residues between amino acids 200 and 343 are required for binding to CHD3 (1676,2000) and C-terminal deletions of ERM indicated that amino acids 279,299 are also required. Furthermore, data from chromatin immunoprecipitation (ChIP) indicate that CHD3/ZFH interacts with the PS1 promoter in vivo. [source] Role of the N-terminal Region in the Function of the Photosynthetic Bacterium Transcription Regulator PpsR,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2008Yoichi Yamazaki PpsR is a transcription repressor for the gene cluster encoding photosystem genes in Rhodobacter sphaeroides. Repression activity is accomplished by DNA binding on the promoter regions of the photosystem gene clusters, and depends on both the redox potential and the presence of antirepressor protein AppA. To understand DNA repression regulation by PpsR, we investigated the function of PpsR domains in self-association for DNA binding. We constructed domain-deletion mutants and verified DNA-binding activity and dimer formation. Gel shift assay for measuring the DNA-binding activity of three sequential N-terminal deletion mutants revealed that N-terminal deletions (of minimum 121 residues) caused loss of binding activity. Size-exclusion gel chromatography revealed that deletion mutant which lacks the N-terminal 121-amino acid deletion mutant to exist as a dimer, although it was less stable than the intact PpsR. The mutants lacking the adjacent regions, Q-linker region and the first Per-Ant-Sim domain, did not form dimers, suggesting the involvement of the N-terminal region in dimer formation. This region is thus considered to be a functional domain in self-association, although not yet identified as a structural domain. Circular dichroism spectrum of the N-terminal region fragment exhibited a ,/, structure. We conclude that this region is a structural and functional domain, contributing to PpsR repression through dimer stabilization. [source] | ||||||||||